Lazzaro was shot multiple times by two masked men in the living room of his Logan home while his daughter was in the room, sparking a decades-long cold case investigation.
“I can confirm after ballistics and forensics that the police are in possession of the firearm used to kill John Lazzaro,” Detective Inspector Cunningham said.
“It has accelerated the investigation. It is a big help for us to find a weapon.”
Acting Superintendent Cunningham said that since 2012, police had identified several people in possession of the unregistered handgun, a Browning 1900 .32 caliber semi-automatic.
The weapon was found in Queensland but has been linked to a man from New South Wales, police said.
“Police have questioned a man, a 45-year-old man, regarding his knowledge of this weapon,” Cunningham said.
“We have determined that a number of people have possessed that firearm since it was used to kill Mr. Lazzaro in 2012.”
Police previously said it was clear that Lazzaro was the target of the violent shooting, but suspects had not been identified.
Police now believe members of the Bandidos Outlaw Motorcycle gang are responsible for Lazzaro’s death.
Investigators confirmed that a renewed call for information in April this year was crucial in containing the case.
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During the public appeal, police released CCTV footage of a tray black ute spotted before the shooting, less than 100 yards from Lazzaro’s South Rochedale home.
“We still believe there are members in our community who are aware of Mr Lazzaro’s death,” Cunningham said.
“I previously announced that the $500,000 reward is still being offered for information leading to the conviction of a person responsible for Mr. Lazzaro’s death.”